Battery Water Level

[Randall Schmidt]

I had my local shop (Zimmerman Marine at Herrington Harbor North in Deale MD) replace two batteries and install an intelligent charger in August of 2016. I was told this charger should remain plugged in when I leave my wetslip to keep the batteries charged without causing overcharge issues associated with chargers that are not intelligent.

Unfortunately though the shop could have sold me maintenance free sealed batteries they sold me batteries that require attention to the water level. Batteries worked fine with no intervention to maintain the water level (my error) till about July of 2018 (a good season and a three-quarters of use) at which time the volt meter showed less than 12 amps. I checked and both batteries were low. I added distilled water (about a half a gallon in total consumed by both batteries) and let her charge. they came back to life showing closer to 13 amps. I checked again Sept 29 after only about 5 - 6 day sails and found the batteries low again. I topped them off again consuming another 1/2 gallon of distilled water. My usage has only been a Raymarine GPS and only one sail on 9/29 with the auto-pilot for about 20 minutes. When I put it on the system warned me the battery was low.

Checking the batteries is a real pain in my 1984 O'day 28 because I need to clear out the substantial contents of my quarter berth to get access. My questions are:
1. Have I done damage to the batteries by not paying attention to the water level for so long?
2. with a properly functioning and well maintained battery how often do I need to check the water levels?
3. Could my intelligent charger be defective and causing the battery water levels to decline so rapidly?
4. Do I replace the batteries with sealed units or upgraded lithium batteries?

 

[Ken Cross]

The low water sounds to me like they are being overcharged (not good). Lead acid batteries shouldn't need a great deal of attention in terms of adding water. It seems like the charger may be the issue. I am assuming you mean voltage when you said amps. If not it would be helpful to know what the voltages are and under what part of the charge cycle you were seeing those amperage levels.

It may also be that you are using an uncalibrated analog voltmeter built into your power panel. If so, get yourself a digital meter and measure with that. Those old style analog meters are often all but useless. I installed a digital panel meter in my last 2 boats and it is a great help.

Ken

 

[Rich Stidger]

IMHO your batteries are trashed. Sorry. When the batteries are allowed to go low enough to require a quart of water in the six cells, the plates have undoubtedly been exposed. This forms a sulfate on the plates that is non-reversible. Additionally you should never have to add that much water at any one time. Over-watering is also bad.
I would recommend replacing the batteries and monitoring the electrolyte level on a monthly basis. Additionally I would check the charger voltage after the batteries are fully charged. This would be the state that should cause the charger to go into a "float" mode. The voltage should be 13.2-13.4V. No higher.
If you are not running any loads (like a fridge), then I would shut off the charger and un-plug from shore power when you are not on-board. I would shut off the battery switch to all of the house loads and only have it connected to the bilge pump. Test your bilge pump to be sure it will run with the battery disconnect switch OFF.
There is no need to keep your batteries on a float charge at all times unless you have small loads that you must run. And being connected to shore power 24/7 is asking for other problems like electrolysis. Just my opinion.
I also think that flooded wet cell batteries that you have are the best bang for the buck. But if maintenance is a real problem, you could put in AGM type that is sealed. But you still want to be sure that the charger is truly in a float mode. And I think the float voltage for AGM is different than for flooded batteries- I'm not sure; I am not an expert on AGM technology. And I would still disconnect the shore power and shut off the main switch as a best practices situation.
These recommendations are worth every penny you paid for them!

 

[Brian D]

Agree with Ken. But it sounds more like your batteries are being boiled off. You might not have the right charger for the batteries you are using. Or possibly to correct setting. You didn't indicate the model of the smart charger. You can help us by telling us what it is and the brand/type of battery (other than wet cell).

It is very possible that your batteries have been damaged.

 

[jssailem]

with @Ken Cross A digital multi-meter. It is an essential tool in maintaining your electrical systems aboard.

Loss of water from your Lead Acid batteries is a critical problem that requires your immediate attention.
At this time I am only guessing the cause. More information is needed. It does not need to be more than a weekend of your time and you can leave the batteries open for inspection not having to move all the stuff.

CAUTION... if after reading this any of it seems too much or not clear to you *** Get a Marine Electrical professional to help***

Put on a pair of eye googles to protect your eyes. Get a rubber glove to protect your hands, and open up the battery caps.
Quick Test: 1 hour charge. looking for battery fluid boiling out.
I would start with adding water to the battery levels (there is supposed to be a little air in the battery. That is why there is a water mark visible when you look down into the battery.
Close the caps and check and record the voltage with your new multi-meter. Be sure the area around the batteries is dry. Turn on the battery charger. leave it to it's job for about an hour. (great time to wash the fore-deck of that bird poop). Occasionally check that the batteries look and smell ok. (no smoke, bubbling out of the caps, things smelling hot.... If any of these turn off everything and let it cool down. Get a Marine Electrical professional to help)
Turn the charger off. Measure and record the voltage after an hour of charging. Examine the top of the batteries and the area around them for moisture. if no moisture present. Eye googles and rubber glove then open up the battery caps and note the level of water..

A second possibility. Battery location. "I need to clear out the substantial contents of my quarter berth to get access." If the batteries are near the edge of your boat (not on the center line) when you sail and heel you could be spilling the battery fluid out. Look for evidence around the base of the batteries by taking them for a 1 hour sail with significant heeling... weeeee
Then inspect the batteries.

Report back or seek a friend in the marina and share a beer while talking about the woes of boat electrical systems.

 

[dlochner]

Modern battery chargers may have different settings for different types of batteries, this is true of the Sterling/ProMariner Pronautic series. The charger may be set to the wrong battery type and thus charging the batteries inappropriately. Also make sure that any sensor connections are set correctly.

As others have said the batteries are probably best used to recover the core charge. Batteries require maintenance, no matter how inconvenient. Mine are located at the bottom of a sail locker, the needs to be emptied and shelf removed to get to them. Not fun, but necessary.

Knowing which battery charger that was installed that will help us.

 

[JamesG161]

12 amps. I checked and both batteries were low. I added distilled water (about a half a gallon in total consumed by both batteries) and let her charge. they came back to life showing closer to 13 amps.

I think there is some confusion going on, at least with me. AMPs? or Volts DC?

If you have a so called "Smart Charger" in use, the only way it is "Smart" controlled is with a "feed back" signal.
It is sometimes called a "Float Charge" and that charge requires a small maintenance Amp flow.
By the PO's description his are Wet Cell.
All Wet Cells require maintenance and typical boat life without a smart charger, correctly set, is 3-5 years with good maintenance. Many hope for 5-8 years.
Jim...

PS: Mine are easily accessible, I check them every month, monitor their amp performance, and plan to change them every 3 years.

 

[JamesG161]

And being connected to shore power 24/7 is asking for other problems like electrolysis. Just my opinion

Unless you check for your boat's Electro-chemical potential using a galvanic reference probe.
Best peace of mind add on to my boat's maintenance...
https://www.boatzincs.com/corrosion-reference-electrode.html
I test my boat in berth and at anchor in the Gulf, every 3 months.

Jim...

PS: Whoops! I just realized mine is due. Thanks SBO posters for the reminder.

 

[jssailem]

@Rich Stidger , @Brian D , and @dlochner are likely all correct. Batteries that are allowed to spill fluid and expose the plates are likely dying or worse.
The questions are:

My questions are:
1. Have I done damage to the batteries by not paying attention to the water level for so long?
2. with a properly functioning and well maintained battery how often do I need to check the water levels?
3. Could my intelligent charger be defective and causing the battery water levels to decline so rapidly?
4. Do I replace the batteries with sealed units or upgraded lithium batteries?

1. Likely. inconclusive information to state with certainty.
2. at least monthly... But you must identify the current state and structure of the batteries. Perhaps more frequently if something is occurring like spillage due to heeling.
3. Not enough information to answer. It is a possibility. As stated need more data about the unit and the settings to give a response.
4. Replacement with led acid may be ok if a regular maintenance practice is followed and you do not have an orientation problem. (See @Maine Sail battery orientation link...https://marinehowto.com/installation-orientation-of-flooded-batteries-on-boats/)
   1. If you keep the same location and choose to a less frequent checking routine than the sealed AGM batteries may be a better fit. (compromise - more money for convenience) Better fit due to the ability to place in the current storage area, but they are not a buy and forget battery. None are. https://marinehowto.com/battery-melt-down-narrowly-averted/ https://marinehowto.com/how-fast-can-an-agm-battery-be-charged/
      
   2. Lithium are a further compromise. More money. Possibly new battery charger (even if the current location is ok as you need a specific charging format to properly charge them.) Again I would refer you to read Maine Sails info... about lithium batteries. https://marinehowto.com/lifepo4-batteries-on-boats/

 

[Don S/V ILLusion]

If you are not going to follow a routine battery check regardless of where they are located, AGMs won't preclude over-charging, under-charging or improper charging.

 

[LeeandRick]

If your batteries are in a place without proper ventilation, like many boats built in the '70s and '80s, I would agree with the above recommendation and replace with AGMs, just for safety. Vented batteries release hydrogen, same gas as the Hindenburg.

 

[JamesG161]

Vented batteries release hydrogen, same gas as the Hindenburg.

Also fuel cell driven craft. OMG I can't believe there are prototype for automobiles. At least on space craft, you have the vacuum of outer space for a Hydrogen release.

Good marine battery compartments are well ventilated.
Jim...

 

[jssailem]

well ventilated.

Does this mean you need a blower vent or that there is ample air around the batteries and that the hydrogen can escape. Because hydrogen will escape from just about everything unless it is in a sealed container.

 

[JamesG161]

Does this mean you need a blower vent or that there is ample air around the batteries

In engineering terms...
Stagnant
No air movement possible, like getting locked in on old Bank Safe. No new Air.

Fresh
Ability of free air movement. You might survive breathing air. It doesn't mean spring time Fresh air.
_____
A battery compartment should allow for Fresh Air movement. Normally 2 way In and Out.
Since Hydrogen gas has a very low explosive limit and Boat batteries have very little Hydrogen production, you can prevent problems by assuring both Ample surrounding Air and at least free air movement.

In addition, maintain your batteries.
Jim...

 

[Don S/V ILLusion]

Does this mean you need a blower vent or that there is ample air around the batteries and that the hydrogen can escape. Because hydrogen will escape from just about everything unless it is in a sealed container.

If the perceived problem was anything but an aberration, we'd all be dead from hydrogen gas explosions. Just look at all the boats designed and built with unventilated battery storage, noteworthy are the almost ubiquitous Catalinas in which the batteries in many of their boats are in/under the floor.

 

[JamesG161]

If the perceived problem was anything but an aberration, we'd all be dead from hydrogen gas explosions. Just look at all the boats designed and built with unventilated battery storage, noteworthy are the almost ubiquitous Catalinas in which the batteries in many of their boats are in/under the floor.

Dang it Don, this is Sunday!!! You make my brain work too much!!
How about...
"Hydrogen gas explosions are unlikely or an insurance scam for boats."
or
"Bull poo poo!"

Just remarking for a friend...
Jim...

PS: Don't smoke and do battery maintenance at same time. Singed eyebrows?

 

[Don S/V ILLusion]

Dang it Don, this is Sunday!!! You make my brain work too much!!
How about...
"Hydrogen gas explosions are unlikely or an insurance scam for boats."
or
"Bull poo poo!"

Just remarking for a friend...
Jim...

PS: Don't smoke and do battery maintenance at same time. Singed eyebrows?

Well stated. My only excuse, flimsy as it is, is that I might be investigated by the FBI for breathing.

 

[JamesG161]

might be investigated by the FBI for breathing.

Hopefully in LESS than a week for sure.

Time to go to the marina and relax with an adult beverage.
Jim...

 

[Davidasailor26]

Also fuel cell driven craft. OMG I can't believe there are prototype for automobiles. At least on space craft, you have the vacuum of outer space for a Hydrogen release.

Good marine battery compartments are well ventilated.
Jim...

Not quite the same. A fuel cell uses hydrogen as the fuel, not in the exhaust. Yes you have a fuel tank full of hydrogen but a fuel tank full of gasoline isn't great either.

 

[Randall Schmidt]

Thanks for your advice. You are right, I meant volts not amps. The bilge pump is hard wired so it works with the battery switch set to off. I will into new batteries and am willing to pay more to lessen the maintenance needs. I've been advised by fellow boaters that I should leave the shore power plugged in and battery charger on as a precaution in case I develop a leak and bilge pump does its job it will eventually draw down the batteries and the water will flow in and sink the boat. This seems to make sense to me so long as the charger is not malfunctioning.